Greets all,
In the interests of knowing exactly what these babies can do, I decided a Dyno run would be a good place to start! Aside from that, I am getting exited about some upcoming mods that I will now be able to compare with. It was done in Melbourne on the 15/11. I would have got this information up sooner, but a trip to Sydney and a busy work have not helped. Here is the low down:
The car:
UZZ31 with just a smige under 140000 on the ticker, built 10/1993.
Running on the Mobil Synergy 8000 98 Octane brew.
Oil is Mobil 1, which is less than 3 months old (with filter!)
Coolant was changed about 2 months ago.
The tests were done in 2nd with ECT on PPPOOOWWWEEEEEERRRRR mode.
The car/dyno was warmed up with 7 reasonable runs. Each time, the peak output increased a little as the oil et al got back up to operating temperature.
The 7th run was in 'Road Trim'(airbox complete and standard) and gave up 128Kw.
The 8th run is the car with the filter in and lid open and gave up about 130Kw.
The 9th run is the car in 'Road Trim'. It yeilded about 128Kw and was just to verify the 8th run. As you can see, its the same as the 7th run.
The big winner though was the 10th run, with no filter and with the lid open which gave a considerable gain right through the curve, peaking at just under 134Kw.
I am slightly kicking myself that we did not do a no filter with the lid closed! Enthusiasm got the better of me?
A few things that were noted:
- With no filter, and no lid the induction noise was LOUD!
- The fuel/air mix was rather rich. According to the Jag guys, at full power it should be about 12.5:1 which is leaner that what my car was at 11.5:1. Ultimate cruising with tailwind it should be in the 14:1 area. Interestingly, it was much worse with the car in road trim, at 11:1. Does this mean with more exhaust flow, this will improve further? Could this be a symptom of a dud O2 sensor not feeding the right information to the ECU? Do O2 sensors die? I also understand that the mixture is rich from the factory.
- Peak power occured from 5600RPM to 5800 RPM approximately before dropping away fairly quickly.
- Fuel cut occurred at 6500RPM
- The torque curve was resonably flat from 3350RPM to about 4500RPM where it started to fall away, peaking at around 4235RPM at 5800N
- There was not a lot of difference with the filter in and lid open but a marked difference with no filter.
- Based on the above, is it safe to say the with filter out with the lid closed would not reveal much of a gain?
- Apparently V12 Jags get 155-165Kw or thereabouts at the wheels.
- The Jag guys could not get over how quiet it was a full load!
- It was not exactly cool in the dyno area. The roller door you can see in the pics is the only entry for cold air. This may have affect the result, but the Dyno is supposed to compensate for that. The fan they used moved the air, but given the relativly small amount of intake space on these cars, it probably was not quite enough... The intake would have been gulping warm air, and the temperature sensor was in the duct leading into the radiator, which I noticed when they were unloading it! You can see temperatures in the files.
- The air filter is still in very good nick. Has not yet started to grey with (I would estimate) less than 2000kms on it.
What does it all mean? Well for one thing, Peter's power calculations based on the 400m speeds are pretty good! I havent done my own yet...
It also means there would be about a 30% drive line loss. It this a lot? We get an extra 2Kw without the lid, with the filter.
We get an extra 6.4Kw and about 200NMs without the lid and without the filter. Peaks remain at the same RPM point in all cases.
With the mixture adjusted and some proper breathing, it would be better!!!
At peak power in Road trim, the mixture was very rich at 11:1.
At peak power without a lid and filter, the mixture was 11.5:1
Interesting eh?
Note that the lower curve in the above graph is the Air/Fuel Mixture.
The next phase will be the installation of the Extractors that I have got from Terry. These look really really good! I will post some detailed pictures of them when my camera has recharged!
See Aaron's car on the dyno after fitting a full exhaust and headers on the ALSC dyno day page.
If any one else has some SOARER V8 dyno graphs and/or the data files for plotting please email me with the specs of your car and the dyno data (pgscott@bigpond.com). cheers Pete
(check out this old link picture!)